import java.util.*;

public class MergeSortedList {
    /**
     * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
     *
     * 
     * @param pHead1 ListNode类 
     * @param pHead2 ListNode类 
     * @return ListNode类
     */
    public ListNode Merge (ListNode pHead1, ListNode pHead2) {
        if (pHead1 == null) {
            return pHead2;
        }
        if (pHead2 == null) {
            return pHead1;
        }
        ListNode head, cur;
        if (pHead1.val < pHead2.val) {
            head = pHead1;
            pHead1 = pHead1.next;
        } else {
            head = pHead2;
            pHead2 = pHead2.next;
        }
        cur = head;
        while (pHead1 != null && pHead2 != null) {
            if (pHead1.val < pHead2.val) {
                cur.next = pHead1;
                pHead1 = pHead1.next;
            } else {
                cur.next = pHead2;
                pHead2 = pHead2.next;
            }
            cur = cur.next;
        }
        if (pHead1 != null) {
            cur.next = pHead1;
        }
        if (pHead2 != null) {
            cur.next = pHead2;
        }
        return head;
    }
}